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          <h1 class="post-title" itemprop="name headline">Java反射</h1>
        

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        <p>本文讲解Java反射的知识<br>视频课程地址：<a href="https://www.imooc.com/learn/199" target="_blank" rel="noopener">https://www.imooc.com/learn/199</a></p>
<a id="more"></a>

<h1 id="Class类的使用"><a href="#Class类的使用" class="headerlink" title="Class类的使用"></a>Class类的使用</h1><h2 id="Class类"><a href="#Class类" class="headerlink" title="Class类"></a>Class类</h2><ol>
<li><p>在面向对象的世界中，万事万物皆对象。</p>
</li>
<li><p><strong>在Java中，除了普通数据类型、静态成员变量方法这2样东西不是对象外，其他一切都是对象。</strong></p>
</li>
<li><p>我们编写的每一个类(本人称为自定义类)，都是java.lang.Class类的实例对象。即<strong>任何一个类都是Class类的实例对象</strong></p>
</li>
</ol>
<h2 id="如何表示Class类的这个实例对象"><a href="#如何表示Class类的这个实例对象" class="headerlink" title="如何表示Class类的这个实例对象"></a>如何表示Class类的这个实例对象</h2><blockquote>
<p>如何表示Class类的这个实例对象: 有三种方式</p>
</blockquote>
<figure class="highlight monkey"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br></pre></td><td class="code"><pre><span class="line"><span class="class"><span class="keyword">class</span> <span class="title">Foo</span>&#123;&#125;</span></span><br><span class="line"></span><br><span class="line">//第一种表示方式：实际告诉我们任何一个类都有一个隐含的静态成员变量<span class="class"><span class="keyword">class</span></span></span><br><span class="line"><span class="class"><span class="keyword">Class</span> <span class="title">class1</span> = <span class="title">Foo</span>.<span class="title">class</span>;</span></span><br><span class="line"></span><br><span class="line">//第二种表示方式：已知该类的对象，则通过getClass方法获取</span><br><span class="line"><span class="class"><span class="keyword">Class</span> <span class="title">class2</span> = <span class="title">foo</span>.<span class="title">getClass</span>();</span></span><br><span class="line"></span><br><span class="line">//第三种表示方式</span><br><span class="line"><span class="class"><span class="keyword">Class</span> <span class="title">class3</span> = <span class="title">null</span>;</span></span><br><span class="line"><span class="keyword">try</span> &#123;</span><br><span class="line">	class3 = <span class="class"><span class="keyword">Class</span>.<span class="title">forName</span>("<span class="title">com</span>.<span class="title">aiolos</span>.<span class="title">reflect</span>.<span class="title">Foo</span>");</span></span><br><span class="line">&#125; <span class="keyword">catch</span> (ClassNotFoundException e) &#123;</span><br><span class="line">	e.printStackTrace();</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>

<h2 id="通过Class类可以创建任何一个类的实例对象"><a href="#通过Class类可以创建任何一个类的实例对象" class="headerlink" title="通过Class类可以创建任何一个类的实例对象"></a>通过Class类可以创建任何一个类的实例对象</h2><figure class="highlight haxe"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br></pre></td><td class="code"><pre><span class="line">Foo foo2 = <span class="literal">null</span>;</span><br><span class="line"><span class="keyword">try</span> &#123;</span><br><span class="line">	<span class="comment">//Foo类需要有无参的构造方法才可以使用此种方式创建实例</span></span><br><span class="line">	foo2 = (Foo)class1.<span class="keyword">new</span><span class="type">Instance</span>();</span><br><span class="line">	foo2.print();</span><br><span class="line">&#125; <span class="keyword">catch</span> (Exception e) &#123;</span><br><span class="line">	e.printStackTrace();</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>

<h2 id="Java类加载机制"><a href="#Java类加载机制" class="headerlink" title="Java类加载机制"></a>Java类加载机制</h2><blockquote>
<p>动态加载类： 指运行时刻加载类————通过动态加载类可以解决使用哪个类加载哪个类，不使用的类不加载<br>静态加载类： 指编译时刻加载类————通过new关键字创建对象是静态加载类，在编译时刻就需要加载所有可能使用到的类 </p>
</blockquote>
<p>Class.forName(类的全称) 这种方式：不仅表示类的类类型，还表示了动态加载类</p>
<p><img src="/blog/images/20191108135017378.jpg" alt="动态加载类"></p>
<h2 id="获取类的成员方法的信息"><a href="#获取类的成员方法的信息" class="headerlink" title="获取类的成员方法的信息"></a>获取类的成员方法的信息</h2><figure class="highlight stata"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">//object是那个类的对象，c就是该类的类类型——底层是通过JNI实现</span></span><br><span class="line"><span class="keyword">Class</span> c = object.getClass();</span><br><span class="line"><span class="comment">//获取类的成员方法信息</span></span><br><span class="line"><span class="comment">/**</span></span><br><span class="line"><span class="comment">* Method类是方法对象的类</span></span><br><span class="line"><span class="comment">* 一个成员方法就是一个Method对象</span></span><br><span class="line"><span class="comment">* getMethods()方法获取的是所有public的方法，包括父类继承而来的</span></span><br><span class="line"><span class="comment">* getDeclaredMethods()获取的是所有该类自己声明的方法，不论访问权限，</span></span><br><span class="line"><span class="comment">* 但不包括从父类继承而来的</span></span><br><span class="line"><span class="comment">*/</span></span><br><span class="line">Method[] methods = c.getMethods();</span><br><span class="line">System.<span class="keyword">out</span>.println(<span class="string">"方法是："</span>);</span><br><span class="line"><span class="keyword">for</span>(int i=0;i&lt;methods.length;i++)&#123;</span><br><span class="line">   <span class="comment">//得到方法的返回值类型的类类型：如int.class、Object.class</span></span><br><span class="line">   <span class="keyword">Class</span> returnType = methods[i].getReturnType();</span><br><span class="line">   System.<span class="keyword">out</span>.<span class="keyword">print</span>(returnType.getName() + <span class="string">" "</span>);</span><br><span class="line">   <span class="comment">//得到方法的名称</span></span><br><span class="line">   System.<span class="keyword">out</span>.<span class="keyword">print</span>(methods[i].getName() + <span class="string">"("</span>);</span><br><span class="line">   <span class="comment">//获取参数的类型：得到的是参数列表的类型的类类型</span></span><br><span class="line">   <span class="keyword">Class</span>[] paramTypes = methods[i].getParameterTypes();</span><br><span class="line">   <span class="keyword">for</span>(<span class="keyword">Class</span> c1: paramTypes)&#123;</span><br><span class="line">	   System.<span class="keyword">out</span>.<span class="keyword">print</span>(c1.getName()+<span class="string">","</span>);</span><br><span class="line">   &#125;</span><br><span class="line">   System.<span class="keyword">out</span>.println(<span class="string">")"</span>);</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>

<h2 id="获取类的成员变量的信息"><a href="#获取类的成员变量的信息" class="headerlink" title="获取类的成员变量的信息"></a>获取类的成员变量的信息</h2><figure class="highlight dart"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment"><span class="markdown">/**</span></span></span><br><span class="line"><span class="comment"><span class="markdown"><span class="bullet">*  </span>成员变量也是对象</span></span></span><br><span class="line"><span class="comment"><span class="markdown"><span class="bullet">*  </span>java.lang.reflect.Field类封装了关于成员变量的操作</span></span></span><br><span class="line"><span class="comment"><span class="markdown"><span class="bullet">*  </span>一个成员变量就是Field类的一个对象</span></span></span><br><span class="line"><span class="comment"><span class="markdown"><span class="bullet">*  </span>getFields()方法获取的是所有public的成员变量的信息</span></span></span><br><span class="line"><span class="comment"><span class="markdown"><span class="bullet">*  </span>getDeclaredFields()方法获取的是该类自己声明的所有成员变量的信息</span></span></span><br><span class="line"><span class="comment"><span class="markdown">*/</span></span></span><br><span class="line"><span class="comment">//Field[] fs = c.getFields();</span></span><br><span class="line">Field[] fields = c.getDeclaredFields();</span><br><span class="line">System.out.println(<span class="string">"成员变量是："</span>);</span><br><span class="line"><span class="keyword">for</span>(Field field: fields)&#123;</span><br><span class="line">   <span class="comment">//得到成员变量的类型的类类型</span></span><br><span class="line">   Class fieldType = field.getType();</span><br><span class="line">   <span class="built_in">String</span> typeName = fieldType.getName();</span><br><span class="line">   <span class="comment">//得到成员变量的名称</span></span><br><span class="line">   <span class="built_in">String</span> fieldName = field.getName();</span><br><span class="line">   System.out.println(typeName+<span class="string">" "</span>+fieldName);</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>

<h2 id="获取类的构造函数的信息"><a href="#获取类的构造函数的信息" class="headerlink" title="获取类的构造函数的信息"></a>获取类的构造函数的信息</h2><figure class="highlight stata"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">Class</span> c = object.getClass();</span><br><span class="line"><span class="comment">//Constructor[] cs = c.getConstructors();</span></span><br><span class="line">Constructor[] <span class="keyword">cs</span> = c.getDeclaredConstructors();</span><br><span class="line"><span class="keyword">for</span>(Constructor constructor : <span class="keyword">cs</span>)&#123;</span><br><span class="line">	System.<span class="keyword">out</span>.<span class="keyword">print</span>(constructor.getName() + <span class="string">"("</span>);</span><br><span class="line">	<span class="comment">//获取构造函数的参数列表：得到的是参数列表的类类型</span></span><br><span class="line">	<span class="keyword">Class</span>[] paramTypes = constructor.getParameterTypes();</span><br><span class="line">	<span class="keyword">for</span>(<span class="keyword">Class</span> class1 : paramTypes)&#123;</span><br><span class="line">		System.<span class="keyword">out</span>.<span class="keyword">print</span>(class1.getName() + <span class="string">","</span>);</span><br><span class="line">	&#125;</span><br><span class="line">	System.<span class="keyword">out</span>.println(<span class="string">")"</span>);</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>

<h1 id="方法反射的基本操作"><a href="#方法反射的基本操作" class="headerlink" title="方法反射的基本操作"></a>方法反射的基本操作</h1><h2 id="如何获取某个方法"><a href="#如何获取某个方法" class="headerlink" title="如何获取某个方法"></a>如何获取某个方法</h2><blockquote>
<p>方法名称和方法参数列表才能唯一决定某个方法</p>
</blockquote>
<h2 id="方法反射的操作-通过Method对象来调用方法"><a href="#方法反射的操作-通过Method对象来调用方法" class="headerlink" title="方法反射的操作(通过Method对象来调用方法)"></a>方法反射的操作(通过Method对象来调用方法)</h2><blockquote>
<p>method.invoke(对象，参数列表)</p>
</blockquote>
<figure class="highlight dart"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br><span class="line">39</span><br><span class="line">40</span><br><span class="line">41</span><br></pre></td><td class="code"><pre><span class="line"><span class="class"><span class="keyword">class</span> <span class="title">A</span></span>&#123;</span><br><span class="line">	public <span class="keyword">void</span> <span class="built_in">print</span>(<span class="built_in">int</span> a, <span class="built_in">int</span> b) &#123;</span><br><span class="line">		System.out.println(a+b);</span><br><span class="line">	&#125;</span><br><span class="line">	</span><br><span class="line">	public <span class="keyword">void</span> <span class="built_in">print</span>(<span class="built_in">String</span> a, <span class="built_in">String</span> b) &#123;</span><br><span class="line">		System.out.println(a.toUpperCase()+<span class="string">","</span>+b.toUpperCase());</span><br><span class="line">	&#125;</span><br><span class="line">&#125;</span><br><span class="line"></span><br><span class="line">public <span class="class"><span class="keyword">class</span> <span class="title">MethodReflect</span> </span>&#123;</span><br><span class="line">	public <span class="keyword">static</span> <span class="keyword">void</span> main(<span class="built_in">String</span>[] args) &#123;</span><br><span class="line">		<span class="comment">//1. 获取 print(int , int ) 方法</span></span><br><span class="line">		<span class="comment">// 要获取一个方法，就是要获取类的信息，获取类的信息首先要获取类的类类型</span></span><br><span class="line">		A a = <span class="keyword">new</span> A();</span><br><span class="line">		Class class1 = a.getClass();</span><br><span class="line">		</span><br><span class="line">		<span class="comment"><span class="markdown">/**</span></span></span><br><span class="line"><span class="comment"><span class="markdown"><span class="bullet">		 * </span>获取方法：方法是由名称和参数列表来唯一决定的</span></span></span><br><span class="line"><span class="comment"><span class="markdown"><span class="bullet">		 * </span>getMethod() 获取的是所有public的方法</span></span></span><br><span class="line"><span class="comment"><span class="markdown"><span class="code">		 */</span></span></span></span><br><span class="line">		<span class="comment">//Method[] methods = class1.getMethods();</span></span><br><span class="line">		<span class="keyword">try</span> &#123;</span><br><span class="line">			<span class="comment">//Method method = class1.getMethod("print", new Class[]&#123;int.class,int.class&#125;);</span></span><br><span class="line">			Method method = class1.getMethod(<span class="string">"print"</span>, <span class="built_in">int</span>.<span class="keyword">class</span>,<span class="built_in">int</span>.<span class="keyword">class</span>);</span><br><span class="line">			</span><br><span class="line">			<span class="comment">//方法的反射操作：即通过method对象来调用这个方法</span></span><br><span class="line">			<span class="comment">//和a.print(10, 20) 调用的效果完全相同</span></span><br><span class="line">			<span class="comment">//方法如果没有返回值则返回null，有返回值则返回具体的返回值类型</span></span><br><span class="line">			<span class="comment">//Object object = method.invoke(a, new Object[]&#123;10,20&#125;);</span></span><br><span class="line">			<span class="built_in">Object</span> object = method.invoke(a, <span class="number">10</span>,<span class="number">20</span>);</span><br><span class="line">			</span><br><span class="line">			System.out.println(<span class="string">"================"</span>);</span><br><span class="line">			Method method2 = class1.getMethod(<span class="string">"print"</span>, <span class="built_in">String</span>.<span class="keyword">class</span>,<span class="built_in">String</span>.<span class="keyword">class</span>);</span><br><span class="line">			method2.invoke(a, <span class="string">"hello"</span>,<span class="string">"world"</span>);</span><br><span class="line">			</span><br><span class="line">		&#125; <span class="keyword">catch</span> (Exception e) &#123;</span><br><span class="line">			e.printStackTrace();</span><br><span class="line">		&#125;</span><br><span class="line">	&#125;</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>

<h1 id="通过反射了解泛型的本质"><a href="#通过反射了解泛型的本质" class="headerlink" title="通过反射了解泛型的本质"></a>通过反射了解泛型的本质</h1><blockquote>
<p>通过Class、Method来认识泛型的本质</p>
</blockquote>
<ol>
<li><p><strong>反射的操作都是编译之后的操作，即运行时的操作</strong></p>
</li>
<li><p>Java中集合的泛型，是防止错误输入的，只在编译阶段有效。绕过编译就无效了</p>
</li>
</ol>
<figure class="highlight gradle"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">public</span> <span class="keyword">class</span> GenericityDemo &#123;</span><br><span class="line"></span><br><span class="line">	<span class="keyword">public</span> <span class="keyword">static</span> <span class="keyword">void</span> main(String[] args) &#123;</span><br><span class="line">		List list = <span class="keyword">new</span> ArrayList();</span><br><span class="line">		</span><br><span class="line">		List&lt;String&gt; list2 = <span class="keyword">new</span> ArrayList&lt;&gt;();</span><br><span class="line">		list2.add(<span class="string">"hello"</span>);</span><br><span class="line">		<span class="comment">//list2.add(2); //错误，无法添加</span></span><br><span class="line">		</span><br><span class="line">		<span class="keyword">Class</span> class1 = list.getClass();</span><br><span class="line">		<span class="keyword">Class</span> class2 = list2.getClass();</span><br><span class="line">		<span class="comment">//反射的操作都是编译之后的操作，即运行时的操作</span></span><br><span class="line">		<span class="comment">//c1 == c2结果返回true说明编译之后集合的泛型是去泛型化的</span></span><br><span class="line">		System.out.<span class="keyword">println</span>(class1 == class2);</span><br><span class="line">		</span><br><span class="line">		<span class="comment">//结论：Java中集合的泛型，是防止错误输入的，只在编译阶段有效</span></span><br><span class="line">		<span class="comment">//绕过编译就无效了</span></span><br><span class="line">		</span><br><span class="line">		<span class="comment">//验证：我们可以通过方法的反射来操作，绕过编译</span></span><br><span class="line">		Method method;</span><br><span class="line">		<span class="keyword">try</span> &#123;</span><br><span class="line">			method = class2.getMethod(<span class="string">"add"</span>, Object.<span class="keyword">class</span>);</span><br><span class="line">			method.invoke(list2, <span class="number">100</span>); <span class="comment">//绕过编译操作就绕过了泛型</span></span><br><span class="line">			System.out.<span class="keyword">println</span>(list2.<span class="keyword">size</span>());</span><br><span class="line">			System.out.<span class="keyword">println</span>(list2);</span><br><span class="line">			<span class="comment">//不能这样遍历，会有类型转换错误</span></span><br><span class="line"><span class="comment">//			for(String s: list2)&#123;</span></span><br><span class="line"><span class="comment">//				System.out.print(s);</span></span><br><span class="line"><span class="comment">//			&#125;</span></span><br><span class="line">		&#125; <span class="keyword">catch</span> (Exception e) &#123;</span><br><span class="line">			<span class="comment">// TODO Auto-generated catch block</span></span><br><span class="line">			e.printStackTrace();</span><br><span class="line">		&#125; </span><br><span class="line">		</span><br><span class="line">	&#125;</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>
      
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                      hits.push({position: position, length: word.length});
                      var wordEnd = position + word.length;

                      // move to next position of hit

                      index.pop();
                      while (index.length != 0) {
                        item = index[index.length - 1];
                        position = item.position;
                        word = item.word;
                        if (wordEnd > position) {
                          index.pop();
                        } else {
                          break;
                        }
                      }
                    }
                    searchTextCount += searchTextCountInSlice;
                    return {
                      hits: hits,
                      start: start,
                      end: end,
                      searchTextCount: searchTextCountInSlice
                    };
                  }

                  var slicesOfTitle = [];
                  if (indexOfTitle.length != 0) {
                    slicesOfTitle.push(mergeIntoSlice(title, 0, title.length, indexOfTitle));
                  }

                  var slicesOfContent = [];
                  while (indexOfContent.length != 0) {
                    var item = indexOfContent[indexOfContent.length - 1];
                    var position = item.position;
                    var word = item.word;
                    // cut out 100 characters
                    var start = position - 20;
                    var end = position + 80;
                    if(start < 0){
                      start = 0;
                    }
                    if (end < position + word.length) {
                      end = position + word.length;
                    }
                    if(end > content.length){
                      end = content.length;
                    }
                    slicesOfContent.push(mergeIntoSlice(content, start, end, indexOfContent));
                  }

                  // sort slices in content by search text's count and hits' count

                  slicesOfContent.sort(function (sliceLeft, sliceRight) {
                    if (sliceLeft.searchTextCount !== sliceRight.searchTextCount) {
                      return sliceRight.searchTextCount - sliceLeft.searchTextCount;
                    } else if (sliceLeft.hits.length !== sliceRight.hits.length) {
                      return sliceRight.hits.length - sliceLeft.hits.length;
                    } else {
                      return sliceLeft.start - sliceRight.start;
                    }
                  });

                  // select top N slices in content

                  var upperBound = parseInt('1');
                  if (upperBound >= 0) {
                    slicesOfContent = slicesOfContent.slice(0, upperBound);
                  }

                  // highlight title and content

                  function highlightKeyword(text, slice) {
                    var result = '';
                    var prevEnd = slice.start;
                    slice.hits.forEach(function (hit) {
                      result += text.substring(prevEnd, hit.position);
                      var end = hit.position + hit.length;
                      result += '<b class="search-keyword">' + text.substring(hit.position, end) + '</b>';
                      prevEnd = end;
                    });
                    result += text.substring(prevEnd, slice.end);
                    return result;
                  }

                  var resultItem = '';

                  if (slicesOfTitle.length != 0) {
                    resultItem += "<li><a href='" + articleUrl + "' class='search-result-title'>" + highlightKeyword(title, slicesOfTitle[0]) + "</a>";
                  } else {
                    resultItem += "<li><a href='" + articleUrl + "' class='search-result-title'>" + title + "</a>";
                  }

                  slicesOfContent.forEach(function (slice) {
                    resultItem += "<a href='" + articleUrl + "'>" +
                      "<p class=\"search-result\">" + highlightKeyword(content, slice) +
                      "...</p>" + "</a>";
                  });

                  resultItem += "</li>";
                  resultItems.push({
                    item: resultItem,
                    searchTextCount: searchTextCount,
                    hitCount: hitCount,
                    id: resultItems.length
                  });
                }
              })
            };
            if (keywords.length === 1 && keywords[0] === "") {
              resultContent.innerHTML = '<div id="no-result"><i class="fa fa-search fa-5x" /></div>'
            } else if (resultItems.length === 0) {
              resultContent.innerHTML = '<div id="no-result"><i class="fa fa-frown-o fa-5x" /></div>'
            } else {
              resultItems.sort(function (resultLeft, resultRight) {
                if (resultLeft.searchTextCount !== resultRight.searchTextCount) {
                  return resultRight.searchTextCount - resultLeft.searchTextCount;
                } else if (resultLeft.hitCount !== resultRight.hitCount) {
                  return resultRight.hitCount - resultLeft.hitCount;
                } else {
                  return resultRight.id - resultLeft.id;
                }
              });
              var searchResultList = '<ul class=\"search-result-list\">';
              resultItems.forEach(function (result) {
                searchResultList += result.item;
              })
              searchResultList += "</ul>";
              resultContent.innerHTML = searchResultList;
            }
          }

          if ('auto' === 'auto') {
            input.addEventListener('input', inputEventFunction);
          } else {
            $('.search-icon').click(inputEventFunction);
            input.addEventListener('keypress', function (event) {
              if (event.keyCode === 13) {
                inputEventFunction();
              }
            });
          }

          // remove loading animation
          $(".local-search-pop-overlay").remove();
          $('body').css('overflow', '');

          proceedsearch();
        }
      });
    }

    // handle and trigger popup window;
    $('.popup-trigger').click(function(e) {
      e.stopPropagation();
      if (isfetched === false) {
        searchFunc(path, 'local-search-input', 'local-search-result');
      } else {
        proceedsearch();
      };
    });

    $('.popup-btn-close').click(onPopupClose);
    $('.popup').click(function(e){
      e.stopPropagation();
    });
    $(document).on('keyup', function (event) {
      var shouldDismissSearchPopup = event.which === 27 &&
        $('.search-popup').is(':visible');
      if (shouldDismissSearchPopup) {
        onPopupClose();
      }
    });
  </script>





  

  

  

  
  

  

  

  

</body>
</html>
